The present exemplary embodiment relates generally to warehouse management systems. It finds particular application in conjunction with identifying the maximal packing density in shifting-tiles automated warehouse and will be described with particular reference thereto. However, it is to be understood that it also finds application in other usage scenarios and is not necessarily limited to the aforementioned application.
Automated warehouses play an increasingly important role in logistics. The current best practice is to design such warehouses in a way where shelves are interleaved with shafts for cranes that can load and unload pallets from the shelves. While this makes controlling the warehouse relatively easy, it does not achieve a very high storage density as one third of the volume of the warehouse is typically required for the crane structure.
One way to improve on this practice is with the addition of pallet moving facilities on the shelves themselves which allows for multi-layer storage of pallets on shelves (or floors). In such a design, the warehouse utilizes shifting-tile floors where each floor consists of a two-dimensional grid of cells, each of which can hold a pallet and can move it to any adjacent cell unless there is a wall between them. The warehouse also includes an elevator located in at least one of the cells connecting the floor with both the loading/unloading port of the warehouse and other floors. Such a design only requires minimal space for the elevator. For instance, on a floor layout with 400 cells and only one elevator, only 1/400th of the space is required for the elevator, increasing the packing density of the warehouse by almost 50% compared to the current best practice.
For example, an automated warehouse including a grid of floor tiles can store and move pallets in a north-south direction and east-west direction. This allows the automated warehouse to achieve a higher packing density. However, to achieve this high packing density, the warehouse needs to be analyzed to determine how densely the pallets can be packed while still ensuring that every pallet can be retrieved. This is made more complicated by the existence of additional constraints, such as walls blocking some movements.
In order to retrieve a pallet from such a warehouse, in most cases, a number of pallets need to be moved around so that the target pallet can reach the elevator. Once there, the pallet can be moved to the loading/unloading port of the warehouse. Whether or not a specific pallet can be moved to the elevator or not depends on 1) the layout of the floor in terms of walls blocking pallets from moving between certain adjacent cells and 2) the number of blank cells on the floor. For instance, if all the cells on a floor are occupied by pallets, only the pallet that is currently on the elevator can be retrieved. As such, a need exists to determine an optimal shifting-tiles floor layout which enables all of the pallets to be retrieved.
The present disclosure provides a new and improved system and method which overcome the above-referenced problems and others.